Meanwhile, Raniere has been hit with child pornography charges. Both Mack and Raniere have pleaded not guilty.

Prior to her arrest, Mack, 35, was last seen chasing after the police vehicle containing Raniere, 57, who was arrested in Mexico and extradited to the U.S. to face trial. Mack is widely known as one of Raniere’s top confidantes.

Authorities have long alleged Raniere led the secretive clan of female followers and brainwashed them into being “sex slaves.” Many women were “branded” with his and Mack’s initials in their pelvic regions, and authorities allege they were coerced into having sex with him.

According to the filed complaint, Raniere (who was known in the group as “The Vanguard”) oversaw the functioning of NXIVM, which operated under an archaic system: women were told the best way to advance was to become a “slave” watched over by “masters.”

They were expected to have sex with their “master” and do any and all menial chores they were ordered to. They weren’t to tell anybody about the arrangement, and they risked public humiliation if they ever revealed details to any party.

Investigators said Raniere preferred exceptionally thin women, so “slaves” had to stick to very low-calorie diets and document every food they ate. As punishment for not following orders, women were forced to attend classes where they were “forced to wear fake cow udders over their breasts while people called them derogatory names,” or threatened with being put in cages, court papers say.

The idea within NXIVM is to continually perpetuate the cycle; each master is supposed to bring in slaves, and then to grow into a master themselves, they need to recruit their own slaves.

Raniere is being held without bail, while Mack is currently out on a $5-million bond and is under house arrest.

Earlier this year, Raniere posted an open letter to the NXIVM website (now deleted), ruing “the picture being painted in the media” about his group and denying any accusations levied against him.

“Over the past months, there have been extensive independent investigations performed, by highly qualified individuals, and they have firmly concluded that there is no merit to the allegations that we are abusing, coercing or harming individuals,” it read in part. “These allegations are most disturbing to me as non-violence is one of my most important values.”

Federal prosecutors announced the new charges against him on Wednesday. There was no immediate response from Raniere’s lawyer.

Raniere and NXIVM have been the subject of criticism for years, dating back to at least 2012 when the Times Union of Albany published a series of articles examining the organization and allegations that it was like a cult.

Other rumoured celebrity members include former Battlestar Galactica star Nicki Clyne and Canadian actor Kristen Kreuk. Clyne has not commented publicly on her involvement, while Kreuk acknowledged hers, saying she’s “disturbed and embarrassed to have been associated” with NXIVM.

NXIVM’s official site still exists, but solely consists of an “important message” to the group’s members. It reads:

“It is with deep sadness that we inform you we are suspending all NXIVM/ESP enrollment, curriculum and events until further notice.

“We will be in touch with more information for anyone currently enrolled in upcoming events/programs.

“While we are disappointed by the interruption of our operations, we believe it is warranted by the extraordinary circumstances facing the company at this time. We continue to believe in the value and importance of our work and look forward to resuming our efforts when these allegations are resolved.”